StandardTrainersCatalog.Sdca Metode

Definisi

Ruang nama:

Microsoft.ML

Rakitan:

Microsoft.ML.StandardTrainers.dll

Paket:

Microsoft.ML v3.0.1

Overload

Sdca(RegressionCatalog+RegressionTrainers, SdcaRegressionTrainer+Options)	Buat SdcaRegressionTrainer dengan opsi tingkat lanjut, yang memprediksi target menggunakan model regresi linier.
Sdca(RegressionCatalog+RegressionTrainers, String, String, String, ISupportSdcaRegressionLoss, Nullable<Single>, Nullable<Single>, Nullable<Int32>)	Buat SdcaRegressionTrainer, yang memprediksi target menggunakan model regresi linier.

Sdca(RegressionCatalog+RegressionTrainers, SdcaRegressionTrainer+Options)

Buat SdcaRegressionTrainer dengan opsi tingkat lanjut, yang memprediksi target menggunakan model regresi linier.

public static Microsoft.ML.Trainers.SdcaRegressionTrainer Sdca (this Microsoft.ML.RegressionCatalog.RegressionTrainers catalog, Microsoft.ML.Trainers.SdcaRegressionTrainer.Options options);

static member Sdca : Microsoft.ML.RegressionCatalog.RegressionTrainers * Microsoft.ML.Trainers.SdcaRegressionTrainer.Options -> Microsoft.ML.Trainers.SdcaRegressionTrainer

<Extension()>
Public Function Sdca (catalog As RegressionCatalog.RegressionTrainers, options As SdcaRegressionTrainer.Options) As SdcaRegressionTrainer

Parameter

catalog

RegressionCatalog.RegressionTrainers

Objek pelatih katalog regresi.

options

SdcaRegressionTrainer.Options

Opsi pelatih.

Mengembalikan

SdcaRegressionTrainer

Contoh

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.ML;
using Microsoft.ML.Data;
using Microsoft.ML.Trainers;

namespace Samples.Dynamic.Trainers.Regression
{
    public static class SdcaWithOptions
    {
        public static void Example()
        {
            // Create a new context for ML.NET operations. It can be used for
            // exception tracking and logging, as a catalog of available operations
            // and as the source of randomness. Setting the seed to a fixed number
            // in this example to make outputs deterministic.
            var mlContext = new MLContext(seed: 0);

            // Create a list of training data points.
            var dataPoints = GenerateRandomDataPoints(1000);

            // Convert the list of data points to an IDataView object, which is
            // consumable by ML.NET API.
            var trainingData = mlContext.Data.LoadFromEnumerable(dataPoints);

            // Define trainer options.
            var options = new SdcaRegressionTrainer.Options
            {
                LabelColumnName = nameof(DataPoint.Label),
                FeatureColumnName = nameof(DataPoint.Features),
                // Make the convergence tolerance tighter. It effectively leads to
                // more training iterations.
                ConvergenceTolerance = 0.02f,
                // Increase the maximum number of passes over training data. Similar
                // to ConvergenceTolerance, this value specifics the hard iteration
                // limit on the training algorithm.
                MaximumNumberOfIterations = 30,
                // Increase learning rate for bias.
                BiasLearningRate = 0.1f
            };

            // Define the trainer.
            var pipeline =
                mlContext.Regression.Trainers.Sdca(options);

            // Train the model.
            var model = pipeline.Fit(trainingData);

            // Create testing data. Use different random seed to make it different
            // from training data.
            var testData = mlContext.Data.LoadFromEnumerable(
                GenerateRandomDataPoints(5, seed: 123));

            // Run the model on test data set.
            var transformedTestData = model.Transform(testData);

            // Convert IDataView object to a list.
            var predictions = mlContext.Data.CreateEnumerable<Prediction>(
                transformedTestData, reuseRowObject: false).ToList();

            // Look at 5 predictions for the Label, side by side with the actual
            // Label for comparison.
            foreach (var p in predictions)
                Console.WriteLine($"Label: {p.Label:F3}, Prediction: {p.Score:F3}");

            // Expected output:
            //   Label: 0.985, Prediction: 0.927
            //   Label: 0.155, Prediction: 0.062
            //   Label: 0.515, Prediction: 0.439
            //   Label: 0.566, Prediction: 0.500
            //   Label: 0.096, Prediction: 0.078

            // Evaluate the overall metrics
            var metrics = mlContext.Regression.Evaluate(transformedTestData);
            PrintMetrics(metrics);

            // Expected output:
            //   Mean Absolute Error: 0.05
            //   Mean Squared Error: 0.00
            //   Root Mean Squared Error: 0.06
            //   RSquared: 0.97 (closer to 1 is better. The worst case is 0)
        }

        private static IEnumerable<DataPoint> GenerateRandomDataPoints(int count,
            int seed = 0)
        {
            var random = new Random(seed);
            for (int i = 0; i < count; i++)
            {
                float label = (float)random.NextDouble();
                yield return new DataPoint
                {
                    Label = label,
                    // Create random features that are correlated with the label.
                    Features = Enumerable.Repeat(label, 50).Select(
                        x => x + (float)random.NextDouble()).ToArray()
                };
            }
        }

        // Example with label and 50 feature values. A data set is a collection of
        // such examples.
        private class DataPoint
        {
            public float Label { get; set; }
            [VectorType(50)]
            public float[] Features { get; set; }
        }

        // Class used to capture predictions.
        private class Prediction
        {
            // Original label.
            public float Label { get; set; }
            // Predicted score from the trainer.
            public float Score { get; set; }
        }

        // Print some evaluation metrics to regression problems.
        private static void PrintMetrics(RegressionMetrics metrics)
        {
            Console.WriteLine("Mean Absolute Error: " + metrics.MeanAbsoluteError);
            Console.WriteLine("Mean Squared Error: " + metrics.MeanSquaredError);
            Console.WriteLine(
                "Root Mean Squared Error: " + metrics.RootMeanSquaredError);

            Console.WriteLine("RSquared: " + metrics.RSquared);
        }
    }
}

Sdca(RegressionCatalog+RegressionTrainers, String, String, String, ISupportSdcaRegressionLoss, Nullable<Single>, Nullable<Single>, Nullable<Int32>)

Buat SdcaRegressionTrainer, yang memprediksi target menggunakan model regresi linier.

public static Microsoft.ML.Trainers.SdcaRegressionTrainer Sdca (this Microsoft.ML.RegressionCatalog.RegressionTrainers catalog, string labelColumnName = "Label", string featureColumnName = "Features", string exampleWeightColumnName = default, Microsoft.ML.Trainers.ISupportSdcaRegressionLoss lossFunction = default, float? l2Regularization = default, float? l1Regularization = default, int? maximumNumberOfIterations = default);

static member Sdca : Microsoft.ML.RegressionCatalog.RegressionTrainers * string * string * string * Microsoft.ML.Trainers.ISupportSdcaRegressionLoss * Nullable<single> * Nullable<single> * Nullable<int> -> Microsoft.ML.Trainers.SdcaRegressionTrainer

<Extension()>
Public Function Sdca (catalog As RegressionCatalog.RegressionTrainers, Optional labelColumnName As String = "Label", Optional featureColumnName As String = "Features", Optional exampleWeightColumnName As String = Nothing, Optional lossFunction As ISupportSdcaRegressionLoss = Nothing, Optional l2Regularization As Nullable(Of Single) = Nothing, Optional l1Regularization As Nullable(Of Single) = Nothing, Optional maximumNumberOfIterations As Nullable(Of Integer) = Nothing) As SdcaRegressionTrainer

Parameter

catalog

RegressionCatalog.RegressionTrainers

Objek pelatih katalog regresi.

labelColumnName

String

Nama kolom label. Data kolom harus Single

featureColumnName

String

Nama kolom fitur. Data kolom harus merupakan vektor berukuran dikenal dari Single

exampleWeightColumnName

String

Nama kolom berat contoh (opsional).

lossFunction

ISupportSdcaRegressionLoss

Fungsi kerugian diminimalkan dalam proses pelatihan. Menggunakan, misalnya, defaultnya SquaredLoss mengarah ke pelatih kuadrat paling sedikit.

l2Regularization

Nullable<Single>

Berat L2 untuk regularisasi.

l1Regularization

Nullable<Single>

Hiperparameter regularisasi L1. Nilai yang lebih tinggi akan cenderung mengarah ke model yang lebih jarang.

maximumNumberOfIterations

Nullable<Int32>

Jumlah maksimum lolos untuk dilakukan melalui data.

Mengembalikan

SdcaRegressionTrainer

Contoh

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.ML;
using Microsoft.ML.Data;

namespace Samples.Dynamic.Trainers.Regression
{
    public static class Sdca
    {
        public static void Example()
        {
            // Create a new context for ML.NET operations. It can be used for
            // exception tracking and logging, as a catalog of available operations
            // and as the source of randomness. Setting the seed to a fixed number
            // in this example to make outputs deterministic.
            var mlContext = new MLContext(seed: 0);

            // Create a list of training data points.
            var dataPoints = GenerateRandomDataPoints(1000);

            // Convert the list of data points to an IDataView object, which is
            // consumable by ML.NET API.
            var trainingData = mlContext.Data.LoadFromEnumerable(dataPoints);

            // Define the trainer.
            var pipeline = mlContext.Regression.Trainers.Sdca(
                labelColumnName: nameof(DataPoint.Label),
                featureColumnName: nameof(DataPoint.Features));

            // Train the model.
            var model = pipeline.Fit(trainingData);

            // Create testing data. Use different random seed to make it different
            // from training data.
            var testData = mlContext.Data.LoadFromEnumerable(
                GenerateRandomDataPoints(5, seed: 123));

            // Run the model on test data set.
            var transformedTestData = model.Transform(testData);

            // Convert IDataView object to a list.
            var predictions = mlContext.Data.CreateEnumerable<Prediction>(
                transformedTestData, reuseRowObject: false).ToList();

            // Look at 5 predictions for the Label, side by side with the actual
            // Label for comparison.
            foreach (var p in predictions)
                Console.WriteLine($"Label: {p.Label:F3}, Prediction: {p.Score:F3}");

            // Expected output:
            //   Label: 0.985, Prediction: 0.960
            //   Label: 0.155, Prediction: 0.072
            //   Label: 0.515, Prediction: 0.455
            //   Label: 0.566, Prediction: 0.500
            //   Label: 0.096, Prediction: 0.079

            // Evaluate the overall metrics
            var metrics = mlContext.Regression.Evaluate(transformedTestData);
            PrintMetrics(metrics);

            // Expected output:
            //   Mean Absolute Error: 0.05
            //   Mean Squared Error: 0.00
            //   Root Mean Squared Error: 0.06
            //   RSquared: 0.97 (closer to 1 is better. The worst case is 0)
        }

        private static IEnumerable<DataPoint> GenerateRandomDataPoints(int count,
            int seed = 0)
        {
            var random = new Random(seed);
            for (int i = 0; i < count; i++)
            {
                float label = (float)random.NextDouble();
                yield return new DataPoint
                {
                    Label = label,
                    // Create random features that are correlated with the label.
                    Features = Enumerable.Repeat(label, 50).Select(
                        x => x + (float)random.NextDouble()).ToArray()
                };
            }
        }

        // Example with label and 50 feature values. A data set is a collection of
        // such examples.
        private class DataPoint
        {
            public float Label { get; set; }
            [VectorType(50)]
            public float[] Features { get; set; }
        }

        // Class used to capture predictions.
        private class Prediction
        {
            // Original label.
            public float Label { get; set; }
            // Predicted score from the trainer.
            public float Score { get; set; }
        }

        // Print some evaluation metrics to regression problems.
        private static void PrintMetrics(RegressionMetrics metrics)
        {
            Console.WriteLine("Mean Absolute Error: " + metrics.MeanAbsoluteError);
            Console.WriteLine("Mean Squared Error: " + metrics.MeanSquaredError);
            Console.WriteLine(
                "Root Mean Squared Error: " + metrics.RootMeanSquaredError);

            Console.WriteLine("RSquared: " + metrics.RSquared);
        }
    }
}